Gate for railway-crossings



(No Model.)

M. B.` MILLS. GATE FOR RAILWAY GROSSINGS.

N0. 333,242. Patented Dec. 29,1885

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UNITED STATES- PATENT FFICE;

MoRT'IMER B. MILLs, oF cHIcAeo, ILLINOIS;

GATE FOR RAI LWAY-CROSSINGS.t

SPECIFICATION forming part of- Letters Patent No. 333,242, datedDecember 29, 18854. Application nieu June e, 1885. serial No. 161,565.(No model.)

.To all whom/vit may concern: l

Be it known that I, MORTIMER B. MILLS, a

Acitizen of the United States, residing at Chicago, in the county ofCook and lState of -Illinois, have invented certain new and usefulImproveinents in Gates for Railroad Crossings; and I hereby declare thefollowing to be a full, clear, and exact description of the same.

My invention relates to the class of gates formed with bars constructedto be swung in vertical planes upon posts properly located at oppositesides of a railroad-track by the application of pneumatic or other forceto open and close them, the swinging of the bars, which are suitablyconnected to beactuated in pairs upon the same side of the track, beingeffected from a single point.

Gates ofthe foregoing description have hitherto been constructed to beoperated by means of pneumatic pressure alone, exerted from a pump, orby liquid-pressure alone, similarly exerted. The first-named medium ofpower, while it affords verygood results, is subject to the objectionthat it requires more perfect con- 2 5 finement within the parts throughwhich it is caused to operate than can be provided without the exerciseof great care and undesirable expense, and even if these parts areoriginally formed perfectlyair-tight they are liable to 3o andapparently of necessity do become leaky, whereby the operation of thegates to be actuated is rendered more or less defective, or they becomepractically, and sometimes even entirely, inoperative. Y This tendencyto 35 leakage from use is mainly attributable to the fact that thepistons in the cylinders employed become dry and loose, permitting theair to leak to an extent which renders it almost, and sometimes quite,impossible to produce suffi- 4o cient pressure to raise or lower thebars. rIhe use of a liquid as the medium of power is objectionable,principally for the reason that it is too heavy for practical purposes,and therefore uncontrollable, and also unreliable for ac- 45 curacy ofoperation.

I find that by using a liquid (preferably oil, since it is not liable tofreeze and affords a desirable lubricator) in immediate contact with thepistons and air intermediately, whereby '50 forcing downward the pistonin the operatingpump causes it to compress the liquid againstv air,which in turn compresses theliquid against To this end my inventionconsists in the general construction of my device; and it also consistsin certain details of construction and combinations of parts, all ashereinafter more fully set forth.

Referring to the drawings, Figure l is a ver-4 tical section through onegate-post and the pump used in operating the same, and showing thepreferred forin of mechanism for operating the bar; and Fig. 2,aperspective view of a portion of a detail. 1

The drawings illustrate the application of my invention to a singlegate-bar, and the following description is confined to such application,though,obviously, by providing several posts-such as the oneillustrated-and the mechanism shown to be connected therewith andhereinafter described, for actuating the bar of each, the air-pipe maybe caused to communicate with the proper feature in each post, and allthe bars may be actuated from a single pump.

F is a gate-post, shown as sunk into the ground, though it and the otherparts hereinafter described may, if preferred, be entirely above groundwithout entailing disadvantages. A gate-bar, D, is supported upon thepost F by means of a shaft, d, to which the vbar is rigidly secured toswing in avertical plane, and is balanced to remain in-any position towhich it is moved. A crank, d', is fastened to the shaft d toward itscenter, and a rod, d2, pivotally attached at one end to the crank d,connects the latter with a crank or pin, d3, provided eccentrically upona ratchetwheel, H, supported to rotate upon a suitable bearing withinthepost, which is preferably hollow, as shown, since if solid the partsalready described and to be hereinafter described would have to beexterior to it.

From the foregoing it will readily be seen that acomplete revolution ofthe ratchet-wheel H from the position shown in Fig. l of the drawingswill raise'the bar D to a vertical position and lower it through thesame arc to a horizontal position.

The raising and lowering of the gate-bar is accomplished by mechanism,of which the fol- IOO lowing is a description: Within the post F, orpartly within it, as shown, is a reservoir, B, containing apiston-cylinder, A', open at its lower end, and preferably so at itsupper f end. The rod b' of the piston a' within the cylinder A'terminates in a rack having loose pawls, pivoted, as already shown inFig. 2 of the drawings, to engage with the teeth of the ratchet-wheel Hwhen the piston a' rises, but to slide over them when the piston falls.A pipe, c c, forms a conduit affording communication between thereservoir B' anda similar reservoir, B, containing the pump mechanism.The latter comprises a cylinder, A, resembling the cylinder A', butlarger and eX- tending into the reservoir B, being preferably cast withthe latter, as shown, and a piston, a, and rod `b, pivoted to a handle,C, to form of the ,latter a lever of the second class, having o ne endpivoted to a fulcrum-bar, e. A desired quantity of liquid, preferablyoil, thoughwater or other liquid may be used, is introduced into thereservoirs B and B'-into the former througha stand-pipe, c', providedwith an ordinary stop-cock, E. The quantity of liquid employed, while itshould not, under any circumstances, be sufficiently great to cause itto pass through the pipe c c' from one reservoir B or B to the other,should be enough to cover the openings on the under sides of thecylinders A and A', and is preferably sufficient within the reservoir Bto fill the cylinder A, and within the reservoir B' to fill it more thanhalf, as shown.

By forcing down the piston a through the medium of the handle C thepressure upon the liquid Within the pump-cylinder A operates to compressthe air or any gas containedV Within the reservoir B and pipe c c2 uponthe liquid contained within the reservoir B', causing it to rise withinthe piston-cylin der A' and raise the piston therein, whereby the pawlson the rod b' engage with the ratchet-wheel H, turning it, and thuscausing the connectingrod d2 to raise the gate-bar. A single strokeofthe pump-handle C may be sufficient to raise the gate-bar froma'horizontal to avertical position, though this is not material, since,as the gate-bar is balanced, it will remain in any position to which itis forced, and if only partly raised by one stroke of the pump, raisingthe handle C will relieve the pressure, causing the liquid below thepiston a to rise with it, and the piston a' to fall by its own weight,since it is not materially obstructed by the pawls upon the rod C',which, as hereinbefore stated, are constructed to slide over the teethof the ratchet-wheel H. In this condition of the parts the bar may beraised farther by again forcing down the handle C, and the operation ofthe pump may be continued till the gate-bar is raised to a verticalposition.

The gatebar is lowered from its vertical position by actuating Vthehandle C in the same manner as to raise it, since, to perform the latteroperation, the wheel H is caused to make a half-revolution, and bycontinuing its rotation, owing to the crank-connection of. the rod d?,the bar will be pulled down in the same arc described by it in itsascent by the rise of the pawls and their consequent engagement with theratchet-wheel incident to the forcing up' ward of the piston a'. Thestop-cock E must of course be closed to permit the gate to be.

operated. v

What I claim as new, and desire to secure by Letters Patent, is

l. In a swinging gate, the combination, with the gate-bar D, of a crank,d', a ratchet- Wheel, H, a rod', d, .connecting the ratchetwheeleccentrically with the crank d', a cylinder, A', having a piston, a',and rod` b', Aprovided with loose pawls to engage with theratchet-wheel, andmeans, substantially as described, for raising thepiston to turn the ratchet-wheel through the medium of the pawls-andactuate the gate-bar, as set forth.

2. In a swinging gate, the combination, with the post F and swinging barD, supported thereon, of a crank, d', secured upon the bearing of thegate-bar to move with it,

a ratchet-wheel, H, supported to rotate uponthe post and connected withthe crank d' by means cfa rod, d, attachedto acrank orvpin, d,providedeccentrically upon the ratchetwheel, a reservoir, B', to containa liquid, a cylinder, A', communicating with the reservoir B', andhaving a piston, a', and rod b', provided with loose pawls to engagewhen the piston is raised with the ratchet-wheel,

and to slide over the same in falling, and a pump communicating with thereservoir B', and operating to force air or other gaseous fluid againstthe liquid contained therein, to raise the said piston, as set forth.

3. The combination, with the swinging bar of a gate, of a reservoir, B',to contain a liquid, a cylinder, A', communicating with the reservoir B'and provided with a piston, means, substantially as described,connecting the said piston with the gate-bar to actuate the same, areservoir, B, to-contain a liquid, and communicating by an air-conduitwith the reservoir B', and a pump communicating with the reservoir B,and operating to compresswthe liquid contained therein through themedium of the air in the conduit against the liquidcontained in thereservoir B' and raise the piston c', as and for the purpose set forth.

4. In a swinging gate, the combination, with the post F and swinging barD, supported thereon, of a crank, d', secured upon` the bearing of thegate-bar to move with it, a ratchet-Wheel, H, supported to rotate uponthe post and connected with the crank d' by means of a-rod, di, attachedto a crank or pin, d3,- provided eccentrically upon the ratchetwheel, areservoir, B', to contain 'a liquid', a cylinder, A', communicatingwithl the reservoir B', and having apiston, a', and rodV b', providedwith loose pawls to engage, when IIO the piston is raised, with theratchet-Wheel, in the conduit against the liquid contained in and slideover the samein falling, a reservoir, the reservoir B and raise thepiston a', as and B, to contain a liquid, and communicating by for thepurpose set forth.

an air-conduit with the reservoir B', and a; MOBTIMER B. MILLS. 5 pumpcommunicating with the reservoir B, Vitnesses:

and operating to compress the liquid eon- BEN B. ATCHERLEY,

tained therein through the medium of the air GEO. W. CASS.

